excess magnesium is reacted with 45 grams of sulfuric acid. 9.5 liters of hydrogen gas are collected understand conditions of temperature and pressure. what is the percentage of hydrogen sulfate and of water in the acod solution?

Answer 1

Mg + H2SO4 ==> MgSO4 + H2
mols H2 = 9.5L/22.4L = 0.5 ESTIMATED so you should redo the calculation as well as all that follow for they are estimates also.
0.5 mol H2 means you started with 0.5 mol H2SO4
g H2SO4 = mols H2SO4 x molar mass H2SO4 = estimated 42 grams
The solution had a mass of 45g, 42 of that was H2SO4 so 3 must have been H2O.
%H2SO4 = (42/45)*100 = ?
%H2O = (3/45)*100 = ?
Remember to recalculate all of these numbers.